1. Field
Aspects of the present disclosure relate to an electrolyte for a lithium rechargeable battery and a lithium rechargeable battery comprising the same.
2. Description of the Related Technology
Lithium rechargeable batteries having high energy densities as a main power sources or supplemental power sources for high power electric devices such as electric vehicles, or hybrid electric vehicles, while exhibiting high performance is under development. Lithium rechargeable batteries including positive materials such as LiCoO2 have a disadvantage in that a high voltage is difficult to achieve in view of energy density. Therefore, research into new positive active materials, which can replace LiCoO2, is under investigation. Particularly, a manganese (Mn) based lithium oxide has received recent attention. However, a conventional electrolyte using LiPF6 as a lithium salt may be decomposed to generate HF when a fully charged cell using a spinel-type positive active material such as a manganese (Mn) based lithium oxide is stored at a high temperature resulting in elution of metal ions. The eluted metal ions may be deposited on the negative electrode surface. Thus, problems, including an increase in the negative electrode potential and a reduction in the open circuit voltage (OCV) of cell, may be posed, resulting in deterioration of the cycle performance and high temperature storage characteristics.